Applicability of the strategies for the elastic seismic analysis of cable-stayed bridges

Several optimized analysis and modelling strategies are provided in this work in order to address the seismic behaviour of cable-stayed bridges in the elastic range, including the expected error ranges in terms of the tower shape, the main span or the stiffness associated with the foundation soil, among other project features. This valuable information for the designer is obtained through the comparative study of different analysis methodologies applied to a large number of cable-stayed bridge models, relating the observed deviations with the simplifications introduced in their mathematical developments. Both the widespread response spectrum analysis, the modal time history analysis and the direct integration of the coupled system of dynamics have been considered. Furthermore, the direct integration has been employed to address the effect of possible contacts and impacts between the deck and the towers during the earthquake in transverse direction. It is concluded that spectrum calculations provide results that are usually 20% lower than the reference modal time history analysis, which is the most precise method. (C) 2012 CIMNE (Universitat Politecnica de Catalunya). Published by Elsevier Espana, S.L. All rights reserved.